Python's `unittest` lacks an `assertHasAttr` method, what should I use instead?
Came up with an answer as I was writing the question. Given a class/test case that inherits from unittest.TestCase
, you can just add a method based on .assertTrue()
:
def assertHasAttr(self, obj, intendedAttr):
testBool = hasattr(obj, intendedAttr)
self.assertTrue(testBool, msg='obj lacking an attribute. obj: %s, intendedAttr: %s' % (obj, intendedAttr))
Duh.
I didn't find anything on google when I was searching before, so I'll leave this here in case anyone else runs into a similar issue.
You can write your own:
HAS_ATTR_MESSAGE = '{} should have an attribute {}'
class BaseTestCase(TestCase):
def assertHasAttr(self, obj, attrname, message=None):
if not hasattr(obj, attrname):
if message is not None:
self.fail(message)
else:
self.fail(HAS_ATTR_MESSAGE.format(obj, attrname))
Then you can subclass BaseTestCase
insteadof TestCase
with tests. For example:
class TestDict(BaseTestCase):
def test_dictionary_attributes(self):
self.assertHasAttr({}, 'pop') # will succeed
self.assertHasAttr({}, 'blablablablabla') # will fail